Periodontal disease is an infection of the root surface of the tooth and the principal cause of adult tooth loss. The inflammatory response adversely affects the surrounding gum and bone tissue and the bacteria may invade these tissues. Periodontal disease can have both local and systemic consequences ranging from sore gums to death. Periodontal disease is currently treated by both medication and surgery. A number of patents are directed to methods and equipment for the treatment of periodontal disease.
U.S. Pat. No. 1,622,616 of Olives Temple, entitled DEVICE FOR APPLYING OINTMENT TO THE GUMS, teaches a device for applying ointment to the inner and outer surfaces of the gums for the treatment of diseases such as pyorrhea The device of the '616 patent has V-shaped arms to which are attached absorbent pads and an ointment applicator. The device both applies ointment to the gums and massages the gums.
U.S. Pat. No. 1,691,785 of Obrin Remensnyder, entitled DENTAL MASSAGE DEVICE, teaches a device for treating diseases, such as pyorrhea, and for exercising and massaging the gums. The device has a compressible elastic base pad which extends up to and contacts the free margin of the gum tissue.
More recent developments in the treatment of periodontal disease have been in the area of diagnostic equipment. U.S. Pat. No. 3,943,914 of James W. Grenfell, Fred M. Sorenson, Hiroshi Ueno, Masato Miyahara, entitled REMOTE-RECORDING PERIODONTAL DEPTH PROBE, teaches an apparatus for the measurement and remote recording of the depth of the gingival sulci and similar anatomical recesses. The apparatus has a depth probe which is ensheathed in a slidable tubular sleeve. The probe is electrically connected to a transducer which can produce a visual record of the sulcus depth at various locations.
U.S. Pat. No. 4,058,115 of Friedrich M. 0. Forster, entitled METHOD AND APPARATUS FOR EXAMINING HUMAN PERIODONAL TISSUES, teaches a method for examining periodontal tissues. The method of the '115 patent requires that force be exerted on the tooth by a rigid medium which slides in a transducer head. The movement of the tooth responsive to the force is measured.
U.S. Pat. No. 4,182,312 of David R. Mushabac, entitled DENTAL PROBE, teaches a dental probe which has a stylus connected through a rod to a three position transducer. Signals are produced indicating the position of the probe. Contact between the tip of the stylus and the patient's tissue completes a circuit which turns on a recording mechanism which receives and records the outputs of the transducers.
U.S. Pat. No. 4,203,223 of Eugene P. Lautenschlager, Peter J. Robinson and Randall M. Vitek, entitled PERIODONTAL PROBE, teaches a force-controlled periodontal probe, having a scale-marked shaft which is covered by a sliding alignment sleeve. Measurements of gingival sulcus depths are made when force is applied to the handle of the instrument. The resistance of the probe to further penetration by the tip portion of the shaft causes the shaft to shift which, in turn, produces displacement.
U.S. Pat. No. 4,250,895 of Sidney Lees, entitled PERIODONTAL PROBE, teaches a periodontal probe for use with a hydraulic pressure system. The probe monitors the flow of gas from the tip to determine the depth of a periodontal pocket.
U.S. Pat. No. 4,340,069 of Ronald N. Yeaple, entitled FORCE-SENSITIVE PROBE AND METHOD OF USE, teaches a method and the mechanical and electronic apparatus for examining a periodontal pocket. The probe of the '069 patent has a moveable lever and a probe tip. The probe tip is inserted into a periodontal pocket and the movement of the tip within the probe body is measured.
U.S. Pat. No. 4,445,857 of Arnoldus J. Borst, entitled DENTAL CAVITY MEASURING INSTRUMENT, teaches an instrument for measuring the depth of a periodontal pocket.
U.S. Pat. No. 4,485,823 of Akiya Yamaguchi, Marvin M. Stark and Kenneth B. Soelberg, entitled APPARATUS FOR DIAGNOSING ENVIRONMENTAL TISSUE OF TOOTH, teaches an apparatus for diagnosing the environmental tissue of teeth to identify the health of the peripheral tissue. The apparatus of the '823 patent senses the frequency band or amplitude of mechanical oscillation transmitted through the tissue.
Current treatment of periodontal disease requires removal of all causative bacterial factors and diseased soft tissue.
In one prior art method, called gingivectomy, the diseased soft tissue (or gum tissue) and also all the health gum tissue is first surgically removed, and then the exposed root is scraped until a smooth root surface is obtained.
Another method known as flap surgery has several variations. Essentially the gum tissue is cut or incised to free the gum from the teeth, the interconnection of the gum between the teeth and the bone. The gum tissue is sliced; folded or deflected away from the tooth; soft tissue, diseased or not, remaining between and around the teeth is removed with knives or by scraping, and then the causative factors are removed by scraping the root of the tooth until the root is smooth. After the root has been scraped, the gum folds or flaps are replaced against the exposed bone and tooth and sutured together. Bone reshaping may also be done. In all methods in which the tooth is scraped a smear layer is formed on the tooth. This smear layer interferes with healing and regeneration.
After the root has been treated by one of the prior art methods such as discussed above a packing is placed over the exposed root area and associated gum tissue.
Substances can be applied to the root surface after mechanical treatment of the root. Citric acid solutions are sometimes used for this purpose. When substances are applied to the root surface additional time and possibly further separation of the gum tissue may be required.
The nature of the gingivectomy and flap surgery procedures are such that areas of the gum much greater in extent than the areas involved with the periodontal disease are involved by the surgical procedure. Additionally these procedures cause a loss of supporting attachment of the gum and bone to the tooth. This can limit the number of times the procedures can be repeated if the disease recurs.
An alternate, but difficult method called root planning or curettage leaves the gum in place. With the gum in place a hand instrument is used to scrape the root of the tooth until the smoothness of the root indicates that the root is free of causative factors. During the procedure adjacent gum tissue may also be removed using the same instrument used to scrape the root of the tooth. Often because of the rigor required to accomplish the removal of causative agents gum tissue may be separated. The separated gum tissue must be sutured. A packing is frequently used for mechanical protection.
These prior art procedures are overly invasive, time consuming and painful. In addition, the incisions and sutures are potential infection sites. Further, since the packing promotes bacterial growth and may interfere with attachment of the gum to the tooth, the healing process is prolonged and may require several weeks. Additional minor procedures in which the sutures and packing must be removed are also required. During the time of healing and for a period of several weeks thereafter the patient must be monitored to assure that healing is progressing and the treated areas remain infection free.